Telegraph converter system and apparatus



Aug. 21, 1951 L. M. POTTS 2,565,267

TELEGRAPH CONVERTER SYSTEM AND APPARATUS Original Filed June "18, 194710 Sheets-Sheet l FIGI I'NVENTOR LOUIS- M. POTTS, DECEASED MARTHA W. G.POTTS, EXECUTRIX ATTORNEY Aug. 21, 1951 1.. M. PoTTs TELEGRAPH CONVERTERSYSTEM AND APPARATUS Original Filed June 18, 1947 FIG. 2

l0 Sheets-Sheet 2 INVENTOR LOUIS M. POTTS, DECEASED MARTHA W. G. POTTS,EXECUTRIX ATTORNEY Aug. 21, 1951 L. M. POTTS 2,565,267

TELEGRAPH CONVERTER SYSTEM AND APPARATUS Original Filed June 18, 1947 10Sheets-Sheet 5 FIG.4

INVENTOR LOUIS M..POTTS, DECEASED MARTHA W. C. POTTS, EXECQTRlX ATTORNEYAug. 21, 1951 L. M. POTTS 2,565,257

TELEGRAPH CONVERTER SYSTEM AND APPARATUS Original Filed June 18, 1947 10Sheets-Sheet 4 9 INVENTQR LOUIS M POTTS,DECEASED MARTHA W. O. POTTS,EXECUTRIX lOl F I G. 6

Ell-7 Aug. 21, 1951 Y L. M. PbTTs 2,565,267

TELEGRAPH CONVERTER SYSTEM AND APPARATUS Original Filed June 18, 1947 10Sheets-Sheet 5 FIG.9

I7 I 2 204 |59- I 6 we 0 0 I25 I63 MI I 203 n7 1 39-4 "All: h

lass-5' 2'||-|\ f 2||-5\ INVENTOR LOUIS M. POTTS,DECEASED v MARTHA W. o.P0TTS,ExEcuTR|x T BY f 296 298 tfil'ORNEY Aug. 21, L. M. POTTS TELEGRAPHCONVERTER SYSTEM AND APPARATUS Original Filed June 18, 1947 10sheets-Sheets 3 FIG. l3

EEBEEHHK Ell-I 22s i INVENTOR LOUlS M. POTTS,DECEASED MARTHA w. c.POTTS,EXEGUTR|X Fl BY 27: I FATTORNEY I l 270 I Aug. 21, 1951 M. POTTS2,565,257

TELEGRAPH CONVERTER SYSTEM AND APPARATUS Original Filed June 18, 1947 10Sheets-Sheet 7 STOPSTARTI2345$$lZ345S SLEEVE l2| ROTATION OFSLEEVESLEEVE MI SLEEVE I42 SLEEVE I95 ATTORNEY Aug. 21, 1951 M. POTTS ITELEGRAPH CONVERTER SYSTEM AND- APPARATUS Original Filed June 18, 194710 Sheets-Sheet 8 lNVENTOR LOUIS M. POTT$,DECEASED MARTHA w.C.POTTS,EXECUTRIX EiTORNEY Aug. 21, 1951 L, M, @OTTS 2,565,267

TELEGRAPH CONVERTER SYSTEM AND APPARATUS Original Filed June 18, 1947 1OSheets-Sheet 9 Fr- Iv 489 (479 U INVENTOR LOUIS M.-POTTS,DECEASED MARTHAw. c. POTTS,EXECUT RIX M mm TORNEY Aug. 21, 1 51 L. M. POTTS TELEGRAPHCONVERTER SYSTEM AND APPARATUS Original Filed June 18, 1947 10Sheets-Sheet l0 .INVENTOR I m E U S A E M X Y E E N D? R s m n N O PC Mw f UH 0 T L R Patented Aug. 21 1951 UNITED STATES PATENT OFFICETELEGRAPH CONVERTER? SYSTEM AND APPARATUS Original application June 18,1947, Serial No.

755,445. Divided and this application Novemher 5, 1948, Serial No.58,502

7 Claims.

seven unit radio signals into five unit start-stop signals.

An additional object of the invention is to provide a motor unit fordriving both converter units mentioned above.

Further objects and advantages of the invention will appear as theinvention is described in 2 detail and restrictions of the scope of theinvention should not be implied from the specific re.- cital'of theabove appearing objects.

According to the parent invention, five unit start-stop signals providedby any conventional nve unit start-stop transmitter are converted intoseven unit radio signals and by means of a radio transmitter are sent toa distant station. At the distant station the seven unit radio signalsare received by a radio receiver and reconverted into the original fiveunit start-stop signals to accordingly operate conventional telegraphrecording apparatus. Use of the seven unit radio code with its errordetecting feature has proved valuable where transmission of codedmessages isrequired. For example, when coded messages are" transmittedin a form such as ABZ, such a group of letters may stand for a phrase,or

even a complete sentence containing several words and receipt of asingle incorrect character may render a message unintelligible or giveto the message a meaning diiierent than was intended. Each codecombination in the seven unit radio code change contains three markingand four spacing impulses. Any deviation in this fixed ratio of thenumber of marking impulses to the number of spacing impulses causes theprinting of an error indication character. A misselection indicator usedfor such a purpose is shown in the United States patent of L. M'. Potts,No. 2,304,120 dated December d, 1942. As will become apparent later inthe description, in the present invention receipt of an all spacingsignal by the five unit start-stop recorder causes the recording of anerror indication character.

The present invention contemplates the use of three basic mechanicalapparatus units, a motor unit, a five to seven unit'codeconversion unit,and a seven to five unit code conversion unit. The motor unit is usedfor driving both converter units or a series of such units. The motorunit in addition to driving the converter unit also drives two sets ofcams which may control various cam operated contacts according to theparticular system in which the motor unit is used. Also included in themotor unit are several phasing and orienting devices which will be takenup later the description.

The five to seven unit code conversion unit includes a single magnetselector which sets up the positions of a series of five unit code bars.The settingof the five unit code bars selects one of a plurality ofcharacter bars which establishes a selection for a series of seven unitcode bars.

The selection of the seven unit code bars is in turn transferred to aseries of seven gooseneck transmitting levers.- Idle signals areautomatically inserted to compensate for the gain of a seven unittransmitting cam sleeve, which continuously rotates, over a five unitstart-stop selector sleeve. It should be mentioned at this time that inthe seven unit radio system the idle signal contains marking impulsesfor the second, fifth and seventh elements of the code combination.

The seven to five unit conversion unit also includes a single magnetselector which sets up the positions of a series of seven unit codebars. The setting of the seven unit code bars selects one of a pluralityof character bars, which establishes a selection for a series oi fiveunit code bars. The setting of the five unit code bars is in turntransferred to a series of five gooseneck transmitting levers. Whenseven unit idle signals are received, the start-stop apparatus is notreleased so that no character will be printed by the five unitstart-stop recorder at this time. If no regular message character or noidle signal characteris received, it is an indication that the ratio ofthree marking impulses to four spacing impulses in the code combinationhas not been maintained. At this time, the gooseneck transmitting leverswill function to send an all spacing signal to the five unit start-stoprecording apparatus and in response to the receipt of such a codecombination an error indication will be recorded,

A more comprehensive understanding of the invention may be had byreference to the following detailed description when read in conjunctionwith the drawings wherein:

Fig. 1 is a plan view of the motor unit;

Fig. 2 is a partial end view of the motor unit;

Fig. 3 is a detailed view of a portion of the motor unit particularlyillustrating a cam sleeve orienting device;

Fig. 4 is a detailed view of a portion of the motor unit showing afinder mechanism;

-Fig. 5 is a detailed view of a cam operated contact device used in themotor unit for synchronizing purposes;

Fig. 6 is a plan view of the five to seven unit code conversion unit;

Fig. '1 is a detailed view of a portion of a mechanism used fortransmitting idle signals in the five to seven unit code conversionunit;

Fig. 8 is an enlarged detailed perspective view, partly exploded, of amechanism used for delaying certain functional operations while idlesignals are being transmitted;

Fig. 9 is a partial end view of the five to seven unit code conversionunit;

Fig. 10 is a detailed view of a part of the idle signal transmittingmechanism;

Fig. 11 is a detailed view, particularly illustrating the single magnetselector utilized in the five to seven unit conversion unit;

Fig. 12 is a detailed view of the character bar bail;

Fig. 13 is a detailed view of the five to seven unit conversion unit,particularly illustrating the mechanism used for storing andtransferring seven unit code signals;

Fig. 14 is a detailed view of the latching levers used for the sevenunit transmitting levers and the idle signal transmitting levers;

Fig. 15 is a timing diagram of the operation of the five to seven unitcode converter unit;

Fig. 16 is a plan View of the seven to five unit code converter unit;

Fig. 17 is a detailed view of the single magnet selector used with theseven to five unit code converter unit;

Fig. 18 is a partial detailed end view of the seven to five unitconverter unit;

Fig. 19 is a detailed view of a finder mechanism used with the seven tofive unit code converter unit;

Fig. 20 is a detailed view of the character bar operating bail of thesame unit;

Fig. 21 is a partial detailed view of the mechanism utilized in the sameunit for transmitting reconverted five unit start-stop signals;

Fig. 22 is a detailed view of a clutch operating mechanism used in theseven to five unit code converter unit.

With particular reference to Figs. 1' to 5, in-

elusive, the motor unit contemplated by the present invention will firstbe described. Numeral I I represents the base of the unit, upon which ismounted a motor I2 which imparts rotary movement to shaft I3 and a gearI4 fixedly carried thereby. Gear I4 is in mesh with a gear I6 supportedupon a hub I1 which is mounted about shaft I8 for relative movement withrespect thereto. By means of an escapement mechanism I9 (to be laterdescribed), gear I6 drives the shaft I8 which is suitably journaled onthe vertically extending supports 2I and 22. Fast to shaft I8 are thegears 23 which are in mesh with gears 24, for the purpose of drivingidentical cam asurges the escapement member in a downward direction asviewed in Fig. 4. Escapement member 29 is provided with a beveledcamming projection 34 and with a driving projection 36 which engages theteeth of a ratchet 31 fixed to shaft I6 by means of a collar 38. Belowshaft I8 is positioned a finder magnet 39 which controls armature 4Ipivoted by means of lugs 42 on a fixed shaft 43. Armature 4I includes anupwardly extending arm 44 having beveled surfaces 46 and 41. A spring 48normally urges armature 41 in a clockwise direction as viewed in Fig. 4.

In accomplishing a finding operation a key 49 is depressed whileincoming idle signals are being received. If marking impulses are notreceived for the second, fifth and seventh impulses as will later bedescribed in connection with the system operations, a relay 5I will beenergized and a circuit will be completed through attracted contacttongue 52 for relay 53 which will lock-up through its contact tongue 54and contact pair 56. As contact tongue 51 is attracted, finder magnet 39is energized and armature 4I moves counterclockwise. Cam 21 is providedwith a groove 58, and as this groove presents itself to beveledprojection 41 of arm 44 of armature M, the armature is free to pivotcounterclockwise, and as it does so, beveled projection 46 carried byarm 44 engages beveled projection 34 of escapement member 29, cammingthe escapement member to the left as viewed in Fig. 4. As the escapementmember snaps back to its original position on its continued rotation,driving projection 36 of the escapement mechanism will engage the nextsucceeding tooth of ratchet 31 so that a change in the drivingrelationship between gear I6 and shaft I8 has now taken place. In otherwords, ratchet 31 has slipped back one tooth with respect to escapementmember 29.. As the armature 4I pivots counterclockwise as just explainedabove, its insulated tail 59 opens the contact pair 56 to break thelocking circuit for relay 53. As long as the apparatus is out of phasewith incoming idle signals, relay 5| will become energized and theratchet 31 will slip back a tooth with respect to escapement member 29in each rotation of gear I6. This presumes that the key 49 will be helddown until a point will be reached whereat relay 5I will no longerenergize and a circuit cannot be completed through contact tongue 52 forthe operation of relay 53. This indicates that the idle signals arebeing properly received and that the apparatus has been br ought intophase with remotely located apparatus. The operation of the escapementmechanism I9 will be better understood when the system descriptions arelater considered. The circuit shown in Fig. 4 is pro vided only for thepurpose of illustrating the mechanical aspects of the operation of theescapement mechanism.

Fixedly secured to shaft I8 is a cam 6I whose periphery is pursued by afollower 62 which is pivoted at 63. The number of lobes on the cam 61may vary with the system in which the apparatus is used so thatinsulated tail 64 carried by the follower 62 may operate contact blade66 back and forth betwen contact blades 61 and 68 a fixed number oftimes in each revolution of shaft I8. The contact blades 66, 61, and 68are associated with a tuning fork phasing ar rangement, the details ofwhich will be described hereinafter in connection with the systems.

Returning now to the cam assemblies 26, a description of an orientingmechanism associated with each of said assemblies will be described.

Cams 69 control contact pairs H at one side of each cam assembly whilecams 12 control contact pairs 13 located at the opposite side of eachcaniassembly. Contact pairs H, 13 are described here for the purpose ofillustration but it will be understood that different numerals will beassigned to the contact pairs shown in the system descriptions as willlater appear. Gear 24 is fixed to a slidable shaft 14 mounted Within acam sleeve 84 and a sleeve 85 which are journaled on ball bearings 15,and 16. A coiled spring 11 urges the shaft 14 to the left as viewed inFig. 3 by pressing against the interior of gear 24. Leftward movement ofshaft 14 is adjustably restricted by means of a lever 18 pivoted at 13.For adjusting the position of shaft 14 a cup shaped dial member BI isprovided which is threaded upon the annular member 82 and the rim 83 ofwhich bears against lever 18. Thus, by turning the dial member 8| theposition of shaft 14 will be adjusted and the relationship between thespiral driving gear 23 and the spiral driven gear 24 may be varied.

Projecting through the cluster of cams 69, 12,

which incidentally are supported on cam sleeve 84, is a dowel pin 80which also projects through a collar 81 fixed to shaft 14. Thus, dowelpin 06 acts as a driving connection to rotate the cam assembly 28.Annular member 82 is provided with a pointer 88 for use in conjunctionwith the graduations 89 inscribed on the dial member 8|. Although thespecific uses of the motor unit will be described later, it is nowapparent that by operation of key 49 the apparatus may be brought intophase with distant apparatus. The orienting mechanism may adjust theapparatus so as to centralize the operation of contact pairs 1 I, 13with incoming signals.

With particular reference to Figs. 6 to 15, a description will now begiven of the conversion unit which converts five unit start-stop signalsinto seven unit continuous signals. Numeral IOI represents a base platewhich supports a front wall I02 and a rear wall I03. Suitably mounted onwalls I02, I03 by means of bearings I04, I06 is a shaft I01. A secondshaft I08 extends between walls I02, I03 and is mounted on the bearingsI09, III. Transverse to shafts I01, I08 there is supported on bearingsH2, H3 a continuously rotating shaft II4 which is suitable coupled toshaft I8 of the previously described motor unit. Carried by shaft II4 isa gear II6 which is in meshv with. a gear I I1 fast to shaft I01. Alsocarried by shaft H4 is a gear II 8 which is in mesh with gear I I9 fastto shaft I08. Thus, by the above described gearing arrangementscontinuous rotary motion is imparted to shafts I01, I08. Forcontributing to the clarity of the description, shaft I01 may beidentified as the five unit shaft while shaft I08 may be called theseven unit shaft.

At the front end of shaft I01 is carried a receiver cam sleeve I2Ioperable under the control of a single magnet selector mechanism I22 ina manner well known in the art. Such a single magnet selector is shownin the United States patent of Zenner No. 1,937,376, dated November 28,1933. Each time a start impulse is received by selector magnet I23, stoparm I24 carried by sleeve I2I is freed for rotation as clutch membersI20 and I25 become effective, and cams I26-I to I28-5 sequentially setfive swords I21 in either a marking or spacing position according toreceived signals. Cam I28 is an armature assist cam which assists theoperation of armature I29 of selector magnet I23, while cam I32 is alocking cam which operates locking lever I33. The function of cams I 28,I32 form no novel part of the present invention and reference should behad to the Zenner patent for a more complete description of theseoperations. As the swords I21 are set their pointed ends press againsteither surface I34 or I36 of associated transfer levers I31 which arepivoted at I38 and have their ends nested in notches of associatedslidable code bars I39-I to I39-5.

Also mounted on shaft I01 are cam sleeves MI and I 42 which areindependently released for a single revolution as will be laterdescribed. Discs I43, I44, and I46 are driving clutch members which arecarried by the shaft I01. Discs I41 and I48 are carried by cam sleeveI4I while discs I49 and I5I are carried by cam sleeve I42. The clutchmembers are provided with the usual felt washer I52, I53, I54, and I56.The entire assemblage just described is spring pressed towards the frontof the apparatus by a coiled spring I51 nested in a hollow portion I58of gear II1. This, of course, is for the purpose of providing thenecessary gripping pressure for the clutch members.

On selector sleeve I2I is secured a cam I59, the periphery of which ispursued by follower arm I II of clutch throwout lever I52 which issuitably pivoted in the apparatus. Clutch throwout lever I02 includes astop arm I03 which is bent over at I04 to engage lug I60 formed as partof disc I51 secured to cam sleeve I4I. Near the end of a revolution ofcam sleeve I2I, follower I5! of clutch throwout lever IE2 is liftedoutwardly by cam i59, freeing stop arm I03 from the path of lug I60 ofdisc I51 and enabling sleeve M! to rotate for a single revolution. Aftersleeve I4I is released, cam I59 places throwout lever IE2 in its firstdescribed position to stop sleeve I4I after it has completed arevolution. Thus, the cycle continues as long as sleeve I2I is rotated.It is understood that sleeve I2I also operates in a start-stop mannerfor each of its rotations.

Sleeve I42 may be released for a single revolution in two differentmanners as will now: be described. Pivotally mounted on fixed shaft IE8is an inverted U-shapedlever I69 having a fol lower arm I1I- which ridesupon a cam I1 2 car'- riedby sleeve MI and an arm I13 which includes astop shoulder I14 which is in thepath of a bent over lug I16 of stopdisc I11 which is suitably fastened to cam sleeve I42. Also pivotallymounted on shaft IE8 is an inverted U-shaped lever I18 having a followerarm I18 which rides upon cam I8I and an arm I82 provided with a lug I83.shaft I68 and includes a depending arm I85 which has formed thereon astop shoulder I81. It will be noted that lug I83 of lever l18'is benttoa osition where it crosses the arm I of lever I84. Stop shoulder I14of lever I09 as shown is in blocking engagement with lug I16 of stopdisc I11. As cam I12 operates follower arm I'll, stop shoulder I14 movesout of the path of lug I10 andsleeve I42 is permitted to move a veryslight distance until lug I 18 abuts against stop shoulder I81 of leverI84. Cam IBI now operates against lever I18 which by means of its lugI83 pushes against arm I88 of lever I84 and stop shoulder I81 is movedout of the path of lug I16 and sleeve A third lever I84 is also mountedon 7 I42 is free to complete its single revolution until again stoppedby shoulder I14 of lever I69. It is thus seen that the successive actionof cams I12, I8I may release sleeve I42.

Sleeve I42 may also be released in a second manner which will now bedescribed. Pivotally mounted on shaft I68 is a lever I68 which includesa depending arm I99 having bent over lug portion I89 which also crossesarm I86 of lever I84. Fastened at I9I- to lever I88 is a link bar I92which at its other end is secured at I93 to a lever I94 which is pivotedat I96 and by means of a follower portion I91 rides upon the cam I98carried upon sleeve I95 mounted on shaft I98. Thus, as the low part ofcam I98 engages follower I91 of lever I94, a spring I99 functions toshift link bar I92 in a direction toward shaft I91, lug I89 of lever I88is moved against arm I86 of lever I84 and stop shoulder I81 is moved outof the path of lug I16 of stop disc I11 carried by sleeve I42. It is,therefore, now apparent that if cam I12 has functioned to operate leverI69 to remove stop shoulder I14 also from the path of lug I16 of stopdisc I11, sleeve I42 is free to rotate providing follower portion I91 oflever I94 is riding the low part of cam I98. The purpose of thisarrangement will appear as the automatic insertion of idle signals islater described.

Returning now to the slidable code bars I39-I to I39-5 the descriptionof the mechanism for converting the five unit signals into seven unitsignals will now be resumed. Mounted on sleeve I42 are function cams29I, 292, 293, and

294. Pivotally mounted on rod I68 is a large substantially U-shaped bail206 which includes a follower projection 291 designed to ride upon thecam 292 under impetus of spring 298. As the high part of cam 292presents itself to projection 291 the lower portion of bail 296 pushesthe individual projections 299 of seven code bars 2I I-I to 2 I I1moving all code bars to the right as viewed in Fig. 13 against theinfluence of their individual springs 2 I2.

Pivotally mounted at 2I3 is a lever 2I4 which is provided with afollower arm 2 I 6 engaging cam 293, and an arm 2 I1 to which ispivotally connected at 229 a stripper bail 2I8. Also pivotallyassociated with stripper bail 2I8 at 2I5 is a lever 2I9 which is pivotedat 22I for the purpose of maintaining bail 2 I 8 parallel when it isoperated. Beneath the stripper bail 2 I8 are pivotally mounted on rod222 a series of character bars 223 which also underlie five unit codebars l39-I to I395 and seven unit code bars 2 I II to H I1. Now asstripper bail 2I8 is operated as follower arm 2I6 of lever 2 I4 isoperated by the high part of cam 293 against the tension of spring 224,all character bars 223 are pushed downwardly against the action ofindividual springs 225 and immediately thereafter the high part of cam292 moves all code bars 2III to 2I I-1 to the right as explained above.'While the bars 2I II to 2I I--1 are still held, follower arm 2I6 oflever 2I4 drops to the low part of cam 293 and a character bar 223selected by an alignment of code bars I39-I to I395 is allowed to dropinto either wide notches 226 or narrow notches 221 of code bars 2I II to2I I1. Now as cam 292 releases bail 296, code bars 2III to 2I I1 whichpresent a narrow notch 221 to a selected character bar 223 will be heldto the right in a marking position. However, those character bars whichpresent a wide notch 226 to the selected character bar 223 will be movedto the left or spacing position by springs 2I2. Now according to theoperation of code bars 2| II to 2I I1, transfer levers 23I which arepivoted at 232 will be set since their depending arms 233 rest inprojections 234 carried by the code bars.

Pivotall carried on rod 238 is a transfer bail 231 which is spring urgedto the right as viewed in Fig. 13 by spring 238 and carries at its lowerend a cross rod 239. On cross rod 239 are mounted selector swords 24I-Ito 24I1 and two idle signal swords 242, 243. Transfer bail 231 includesa follower arm 244 which rides upon cam 246 mounted on cam sleeve I ofshaft I98. Thus, as the high part of cam 246 engages follower arm 244,transfer bail 231 is rocked back and forth and swords 24II to 24I- -1acquire a selective setting from transfer levers 23I in conventionaltelegraph fashion. Swords 24II to 24I1 will now engage either surface241 or 248 of latching levers 249-I to 249-1 which are pivoted at 259.Mounted on rod 269 are a pair of lock bails 252, 253 having respectivefollower arms 254, 256 for engaging respective cams 251, 258. Lookingbails 252, 253 are provided with the usual blades 259 which may engageeither side of a projection 26I formed on latching levers 249I to 2491.When the high part of cam 258 engages follower 256, bail 253 freeslatching levers 249I to 249--3 and an idle signal latching lever 219 foroperation. When the high part of cam 251 engages follower arm 254 ofbail 252, latching levers 2494 to 249-1 and an idle signal latchinglever 265 are freed for operations. When the latching levers are freedfor operation as just described, they assume the position of theirassociated swords 24II to 24I1 and accordingly their shoulders 259 blockor unblock associated gooseneck transmitting levers 26Il to 26I-1 whichare mounted on rod 262. Thus, transmitting levers 26II to 26I-1 mayeither close transmitting contact pairs 263-I to 263-1 and send amarking signal or allow the contact pairs to remain open and send .aspacing signal when operated by their respective cams 264--I to 264-1.In a like manner, idle signal latching levers 219, 265, respectively,control the operation of idle transmitting levers 266, 261 which arerespectively operated by cams 263, 269. Transmitting lever 266 isadapted to send a marking impulse for the second element of the code andtransmitting lever 261 is adapted to send marking impulses for the fifthand seventh elements of the code. However, it should be pointed out thatidle signal latching levers 219, 265 are differently shaped and arerespectively provided with projections 21I, 212 which block alltransmitting levers 26I-I to 26I1 from operation when the idle signal istransmitted as will be later described. This is accomplished asprojections 21I, 212 are moved to a position to block the depending arms213 of the transmitting levers 26II to 26I1.

The mechanisms involved in the automatic transmission of idle signalswill now be described, with particular reference to Fig. 10. Mounted onrod I68 is a large U-shaped locking bail 211. Pivotally carried at 218by bail 211 is a follower lever 219 which rides upon cam 294. Attachedto follower 219 by means of pivot screw 282 is a link bar 283 which isslotted at its opposite end as indicated by numeral 284 to receive bolt286 carried by a follower arm 281 which is pivoted at 288 and rides uponcam 289. When the high part of cam 284 presents itself to follower 219and the apex of cam 289 presents itself to follower functions to releasesleeve I 4|.

281, link bar 283 is shifted to the left as shown in Fig. 10. When thisoccurs, locking blade 290 of bail 211 is freed from projection 29I of anidle signal control lever 292 which is pivoted at 293. However, iffollower 219 is on the high part of cam 294 and follower 281 is on thelow part of cam 289, follower 281 does not exert the additional motionwhich is necessary to shift link 283 far enough to the left to free theidle signal lever 292. By the same token, when follower 219 is on thelow part of cam 284 and the follower 281 rides the apex of cam 289,again insufficient motionis imparted to link bar 283 to free the idlesignal lever 292.. In other words, the sum of the motions produced bythe high part of cam 284 and theapex of earn 289 is necessary to shiftlink bar 283 sufiiciently to free idle signal lever 292.

- Also pivoted at 293 is a divide pawl 294 which rides upon the cam 2|.It is so termed because operation of divide pawl 294 determines whetheran idle or. a message signal will be transmitted. In the position shownin the drawings, idle lever 292 is locked in its message or lineposition by blade 298 of bail 211. Also, divide pawl 294 is shownlatched up on shoulder 296 of a latching lever 291 which is pivoted at298 and urged in a clockwise direction by spring 299. A spring Sill.interconnects divide pawl 294 and idle signal lever 292 while a lighterspring 392 tends to urge idle signal lever 292 counterclockwise. Now ineach revolution of cam2 I, the apex of this cam operates divide pawl 294to latch it up on latching lever 291. Also in each revolution ofcontinuously rotating cam sleeve I95 the cam 246 operates transfer bail231, and near the end of its stroke, after a selection has beentransferred, a portion of the bail 289 strikes latch 291 and therebyreleases divide pawl 294.

With reference now to the timing diagram (Fig. a resume of the variousoperations will be given and the automatic insertion of idle signalswill be explained. Five unit start-stop signals .are received byselector magnet I23, as sleeve I2I is rotated. Approximately duringreceipt of the fifth impulse by selector magnet I23, cam I59 Now, assumemessage signals are being transmitted, cam I98 mounted on sleeve I95carried by seven unit shaft I98 will function to release sleeve I42 inconjunction with cam I12 of sleeve MI in a manner explained inan earlierportion of the specification. It should be remembered that sleeve I95 isa continuously rotating sleeve, while sleeve I 42 is a start-stopsleeve. Therefore, sleeve I95 is continuously gaining on sleeve I42.

' Now as sleeveI42 is released, cam 203 operates stripper bail 2I8 andall character bars 223 are moved downwardly. Cam 292 now functions to.move all code bars 2! l-I to 2| I1 to the right as described. Aselected character bar 223 is operated. as the low part of cam 293 ispresented to lever 2M and swords 24II to 24I1 are set in their selectedpositions. Game 289 and 284 combine to unlock idle signal lever 292 byoperation of bail 211. Directly after cam 289 operates, cam 245 operatesto transfer a new setting to swords 24I-I to 24I--1 by operating bail231. 251, 258 function successively to enable latching'levers to acquirethe new setting as bails 252, 258 are operated. This new setting istrans- :mitted immediately thereafter as shown in the timing chart.Prior to the operation of bail. 231,

divide pawl is latched up on latch 291 by operation of cam 29! and isagain tripped by bail .231 near the end of its stroke so that it ridesagain on the low part of cam 29L Now as long as cam 246 of the sevenunit sleeve I is operating later than cam 29I of start-stop sleeve I42,idle signal lever 292 will be retained in its live or message signalposition during a transfer since with divide pawl 294 latched up onlatch 291, spring 38I is distended and tends to pivot idle signal lever292 clockwise. It is assumed in the present description that sleeve I95and sleeve I42 are moving towards the left in the timing diagram andthat the apex of cam 289 is at this time in line with the high part ofcam 284. After a series of cycles the apex of cam 289 will be operatingin step with the low part of cam 294 and obviously bail 2?! cannotunlock idle signal lever 292 at this time. Now as cam 289 continues togain on cam 284, a point will be reached where the apex of cam 289 willagain function in step with the high part of cam 294. This is anindication it is now time to insert an idle signal which must beinserted without losing a signal stored on transfer levers 23I. In otherwords, transfer of the stored signal must be delayed as will hereafterappear while an idle signal is transmitted and such an operation must beaccomplished without loss of any message signals.

When seven unit sleeve I95 has gained on sleeve I42 to the point wherethe apex of cam 299 again operates in conjunction with the high part ofcam 294 to unlock idle signal lever 292, idle signal lever will now bemoved to its idle position by spring 39L Now as the transfer is made bybail 281, idle signal swords 242, 243 will be set in their idlepositions. Bail 231 will again attempt to trip latch 291 at the end ofits stroke but it will be ineffective since latch 291 will still betripped from the previous cycle. These just described operations weremade possible since divide pawl 294 is now operated at this point afterthe transfer has been made by bail 231 and after latch 291 wasineffectually operated.

While message signals were being transmitted, cams I98 and I12 wereeffective to release sleeve I4! as explained However, the release ofsleeve I42 is now delayed as the idle signal is transmitted. Thecombined action of cams I12 and I8I of sleeve I II will now be necessaryto release sleeve I42. When idle signal sword 242 moves to its idleposition, projections 3 of idle signal latching levers 219, 26 5 moveinto the path of projection 3I2 of lever I 94 so that cam followerprojection I91 of lever I94 cannot move to the low part of cam I98 and,therefore, link bar I92 cannot function to release cam sleeve I42 inconjunction with cam I12. In other words, sleeve I42 cannot be releaseduntil cam I8I operates after cam I12. During this time sleeve I95 makesa further gain on sleeve I42 due to the delay in releasing sleeve I42.At this time the idle signal is being transmitted by idle transmittinglevers 299, 281, while transmitting levers 26I-I to 29I1 are blocked byprojections 21I, 212 of latching levers 219, 285. Now, while the idlesignal is being transmitted, cam 29I will function to reset divide pawl294. The apex of cam 289 will again be in step with a high part of cam294 so that before cam 24-9 operates to make the signal transfer, dividepawl 294 by means of spring 299 will move idle signal lever 292 to itslive or message position. As the idle signal transfer is made byoperation of cam 248 and bail 231, the signal which was delayed will notnow be transferred. It will be noted that this isaccomplishedapproximately in the latter half of the transmission of thesixth element of the idle signal. It will be further noted that cams258,

251 function immediately afterward to operate bails 252, 256 and permittransmitting levers 26|i to 26l-1 to acquire the delayed message codecombination and now transmit the delayed signal. During this intervalwhen the above transfer was made, the idle signal swords 242, 243 weremoved to their idle position and levers 210, 265 were accordinglyoperated so that projections 3!! of levers 210, 265 no longer blocklever !94 from operation. However, now the high part of cam !08 holdsthe follower projection I91 of lever i94 so that the sleeve I42 cannotbe released by the combined action of cams I12 and I98. However,immediately thereafter the low part of cam I98 will present itself tothe follower projection !91 of lever I94 and the sleeve I42 will nowagain be released in successive cycles by the operation of cams I12 and!98 until it is time to insert another idle signal. It may be furtherobserved that while the release of sleeve M2 was delayed, the operationof cams 203, 202 carried thereby was also delayed so that the setting ofthe code bars 2!!! to 2! and transfer levers 23! in accordance with theneXt following message signal was also temporarily deferred. Such atransfer now occurs immediately after the preceding delayed signal istransferred to swords 24!! to 24!1 by operation of cam 246 and bail 231.Thus, there is no loss of signals when the idle signal is inserted. Itwill be noted that when cam sleeve !42 is at a complete rest andstartstop signals are being converted, a high part of cam 204 presentsitself to follower 219 of bail 211 so that the idle signal lever 292 maybe re leased to its idle position for the transmission of a series ofidle signals. Divide pawl 294, of course, will not be operated with camsleeve !42 idle and it will remain continuously in its tripped positionunder these conditions.

Having reference now to Figs. 16 and 22, a description will be given ofthe converter unit which converts seven unit continuous signals intofive unit start-stop signals. Numeral 40! represents the base of theunit upon which is suitably mounted end walls 402, 403. On bearings 404,406 secured to end walls 402, 403, respectively, is mounted shaft 401,while on bearings 408, 409 secured to end walls 402, 403, respectively,is mounted shaft 4! Suitably mounted on bearings 4|2, 4|3 is a shaft 4|4which is coupled in any conventional manner to the motor unithereinbefore described.

Fast to shaft M4 is a gear 416, which is in mesh with a gear 4! 1carried about the shaft 4! The relationship of shaft M4 to gear M1 isadjustable by means of a finder arrangement to be later described whilethe position of a seven unit receiving cam sleeve 4|8 may be adjusted bymeans of an orienting mechanism now to be described. Gear 4|1 haspivoted thereon at 420 a pawl 4!!) which is normally spring pressed intoengagement with a ratchet 42! secured to shaft 4! Projecting fromratchet 42! is a pin 422 which engages in a spiral slot 423 carried by aout like member 424 which is suitably secured to cam sleeve 4|8. Shaft4!! is slidable in bearings 408, 409 and is normally urged to the leftby a lever 426 which is pivoted at 421 and urged counterclockwise byspring 428. At its front end, shaft 4! is engaged by a lever 429 againstwhich bears a cam surface 43! of a pivoted indicator 432 mounted onorienting plate 433. Plate 433 is similar to plate shown in Fig. 4 ofUnited States Patent No. 1,904,164 of Morton et al. dated April 18,1933. Plate 433 is provided with the usual graduations (not shown) andthus an operation by grasping the handle 434 of pivoted indicator 432may vary the position of shaft 4. This causes pin 422 to move in thespiral slot 423 of member 424 to rotate member 424 and causes the sleeve4 l 8 therefore to be adjusted with respect to shaft 4! or more properlywith respect to the incoming signals.

Operation of a finder mechanism associated with this conversion unitwill now be described. The finder mechanism operates in a somewhatsimilar manner to the finder mechanism described in connection with themotor unit. It will be understood that both the finder mechanisms maynot have to be used. The finder mechanism about to be described may findutility if a separate motor were used to drive the seven to five unitcode conversion unit, rather than the motor unit previously described.As described above, pawl 4|9 carried on gear M1 is in engagement withratchet 42! and thereby drives ratchet 42!. Operable by a finder magnet436 is an armature 431 having a follower arm 438 and a pawl tripping arm44! the armature being pivoted on rod 442. When finder magnet 436 isenergized due to failure of the apparatus to be in phase with apparatusat a remote station in response to the receipt of idle signals, thearmature 431 is attracted and when groove 443 of a cam 444 carried onsleeve 445 presents itself to follower arm 438, the follower arm 438will drop into the groove and the free end of pawl tripping arm 44! willmove into the path of pawl 4!!! and cause the pawl to be tripped andengage the next succeeding tooth of the ratchet so that the drivingrelationship between gear M6 and cam sleeve 4 8 has been altered. Thisoperation is cyclically repeated until the correct phase is established.There are seven teeth on the ratchet 42! which represents the seven codeelements of a signaling code combination. Thus, the finder mechanism maybe used for phasing the apparatus with respect to incoming signals whilethe orienting device can be used for adjusting cam sleeve 4|8 within theindividual impulses. Contact pair 448 is operated in a manner similar tocontact pair 56 which was described in connection with the findermechanism included with the motor unit.

Also carried on shaft M4 is a gear 45! which is in mesh with a gear 452carried on shaft 401. For the purpose of the present description shaft4!! may be referred to as the seven unit shaft and shaft 40'! may beconsidered to be the five unit shaft. Incoming continuous seven unitsignals are received by the selector magnet 453 which is part of asingle magnet selector 454. As the signals are received the seven swords456 are set in the usual manner according to the nature of the receivedimpulses by the sequential operation of cams 451-! to 451-1 carried byreceiving cam sleeve 458. In addition, cam sleeve 458 carries lock cams459, 46! which respectively operate lock bails 462, 463 during receiptof the seventh and first impulses of a code combination. Bails 462, 463are both pivoted on the rod 464 and are provided with the usual springs465 for enabling the bails to follow the periphery of their cams bymeans of their respective follower arms 466, 461. Each bail is providedwith a locking blade 468 designed to engage either side of projections469 carried by locking levers 41!-! to 41!1.

Bail 462 controls locking levers 41!-! to 41|--3- and bail 463 controlslocking levers 41!4 to 41!1. The pointed end of swords 456 may engageeither surface 412 or 413 of associated lock levers 41!--| to 41!1 andaccordingly op- 13 erate the lock levers about the pivot 414 when thelocking bails 482, 483 are operated. The lower ends of levers 4111 to411--1 are engaged in notches 416 of associated notched seven unit codebars 411--1 to 411-1. Underlying the seven unit code bars 411-1 to 4111and the five unit code bars 4181 to 418- are a series of char acter bars419 which are pivoted on rod 421 and urged upwardly by individualsprings 481.

Carried on sleeve 418 is a cam 482 which in each cycle of operationsrocks the follower 483 about its pivot 484. Follower 483 is urgedclockwise by means of a spring 481 and is pivotally connected at 488with stripper bail 489. For maintaining parallelism, bail 489 ispivotally connected at 491 with a lever 492 which is pivoted at 499. Asthe high part of cam 482 works against follower 483, all character bars419 are moved downwardly and while they are so held a cam 493 operates afollower 494 about its pivot 495 against the tension of spring 496 topush all code bars 418-1 to 4185 to the left by reason of the engagementof follower 494 with projection 491 of the code bars. Follower 483 nowdrops off the high part of cam 482 while code bars 418-1 are held to theleft and a selected character bar 419 now moves into an alignment ofnotches. in code bars 411-1 to 411-] and into an alignment of widenotches 498 and'narrow notches 499 of code bars 418-1 to 418-5. Now whenfollower 494 drops to the low part of earn 493, code bars 4181 to 4185having wide jnotches 498 in engagement with the selected character bar419 will be allowed to be drawn to the right or spacing position byindividual springs 591, while those having narrow notches 499 will beretained to the left in marking positions. Pivotally supported at 592 onindividual code bars 419-1 to 418-1 are latches 593, which are springurged to the left by individual springs 594. Formed on latches 593 arebifurcations 596 which straddle the lower end of a latching lever 591which is pivoted at 598. At its upper end, each latching lever 591 isprovided with a projection 599 designed to be engaged at either side byblade 511 of locking bail 512 which is pivoted on rod 513 and urgedcounterclockwise by spring 514. Bail 542 includes a follower arm 516which rides upon cam- 5 I 1 carried by transmitting sleeve 518 of shaft491. When bail 512 is operated, latching levers associated with codebars 418-1 to 418--5 set in spacing position will be in the positionshown and shoulders 519 of lever 591 will prevent closure oftransmitting contact pair 521- by transmitting gooseneck lever 522 whencam sleeve 5! 1 and cams 529-4 to 5295 are released. On the other hand,upon operation of bail 512, those code bars 418-1 which are in markingposition to the left by means of springs 594 will now cause levers 593to pivot slightly counterclockwise thereby withdrawing shoulder 519 fromthe path of transmitting gooseneck levers 522 and enable closure oftransmitting contact pairs 521-4 to 5215 when cam sleeve 5 I 8 isreleased for operation. It should be pointed out that as a code bar4181, for example, is moved to the left, spring 594 is placed undertension and tends to draw lever 593 counterclockwise but cannot do sountil bail 512 is operated. This makes possible a signal overlaparrangement to hold a signal code combination by means of code bars418-1 to 4185 until bail 512 is operated.

The means of releasing the transmitting sleeve 518 by operation ofclutch 515 will now be described. Carried by sleeve 519 is a releasedisc 524 which in the rest position of the sleeve, has a high partinengagement with stop arm 525 of the clutchv lever 526'which is pivotedat points 521 and urged in a clockwise direction by spring 528.Pivoted'at 529 is a follower 531 which is urged clockwise by a spring532 and rides upon a cam 533 carried by sleeve 418 of shaft 4. In theposition shown, follower 531 holds a slidable bar 534 to the left.However, when follower 531 is operated by earn 533, aspring 538 pullsbar 534 to the right and a projection. 531 formed thereon engages tail538 of clutch lever 529 to thereby release cam sleeve 518. When an idlesignal is received, idle character bar 539 will move into notch 541 ofbar 534 to thus prevent the release of cam sleeve 518.

A typical conversion operation by means of the seven to five unitconverter will now be briefly described. A seven unit signal codecombination is received by selector magnet 453. During re ceipt of thesixth element of the code, bail 458 operates and code bars 411-1 to411-3 are set. During the next following first element period ofthe'code, bail 461 operates and code bars 411-4 to 411-! are set.Immediately thereafter, cams 492 and follower 483 function together withcam 493 and follower 494- as'explained to enable code bars 418-4 to 4185to receive the converted selection. Approximately during the fifthelement period of the seven unit code, cam 539 functions to releasecamsleeve 518. Immediately thereafter bail 512 operates and freeslatching levers 591. The five unit start stop signal is transmitted ascam sleeve 519 is released. It should be mentioned that the usualstart-stop transmitting cam 549 is provided on sleeve 518. If anincorrect signal is received bythe seven unit selector which is notcomposed of three marking and four spacing impulses, the five unitstart-stop sleeve 518 will be released and an all spacing signal will betransmitted as no character bar is selected at this time since all codebars 418--1 to 4185 will move to their spacing positions. Receipt of anall spacing signal by the five unit receiving station will cause'theprinting of an error indication character.

What is claimed is:

1. In a telegraph converter apparatus, selector means responsive tosignal code combinations each composed of start-stop and a series ofequal length signals, a series of code bars positionable by saidselector means in response to receipt of said signal code combinationsby said selector means, a series of character bars individuallyselectable according to the operation of said code bars, a second.series of code bars controlled by said individually selectable characterbars, a series of transmitting elements individual to said second seriesof code bars and controlled by the setting thereof for transmittingcontinuous code combinations composed of equal length impulses whichcorrespond to related code combinations having start-stop impulses, saidcontinuous code combinations being transmitted at a greater rate ofspeed than said start-stop impulses are received by said selector means,means for transmitting idle signal combinations periodically tocompensate for the greater rate of transmission of said continuous codecombinations, and means for rendering said transmitting elementsinoperative while said idle signals are being transmitted.

2. In a telegraph converter apparatus, selector means responsive tosignal code combinations,

' each composed of start-stop and a'series of five equal lengthimpulses, a series of five code bars positionable by said selector meansin response to the receipt of said signal code combinations by saidselector means, a series of character bars individually selectableaccording to the operation of said code bars, a series of seven codebars selectively controlled by said individually selectable characterbars, a series of transmitting elements individual to said seven codebars and controlled by the setting thereof for transmitting continuouscode combinations composed of seven equal length impulses, saidcontinuous code combinations being transmitted at a greater rate ofspeed than the start-stop impulses are received by said selector means,means for transmitting idle signal code combinations periodically tocompensate for the greater rate of transmission of said continuous codecombinations, and means for rendering said transmitting elementsinoperative while said idle signals are being transmitted.

3. In a telegraph converter apparatus, a single magnet selectorresponsive to signal code combinations, each composed of a start-stopand a series of equal length impulses, a first series of code bars equalin number to the number of said equal length impulses and controlled bysaid single magnet selector in response to the receipt of said signalcode combinations, a series of character bars individually selectableaccording to the operation of said code bars, a second series of codebars greater in number than the number of code bars of said first seriesof code bars and selectively controlled by said individually selectablecharacter bars, a series of transmitting elements individual to saidsecond series of code bars and controlled by the setting thereof fortransmitting continuous code combinations composed of equal lengthimpulses, means for enabling said transmitting elements to transmit saidcontinuous code combinations at a greater rate than corresponding signalcode combinations are received by said selector, means for transmittingidle signal code combinations periodically to compensate for saidgreater rate of transmission, and means for rendering said transmittingelements inoperative While said idle signals are being transmitted.

4. In a telegraph converter apparatus, a single magnet selectorresponsive to signal code combinations, each composed of a start-stopand a series of equal length impulses, a first series of code bars equalin number to the number of said equal length impulses and controlled bysaid single magnet selector in response to the receipt of said signalcode combinations, a series of character bars individually selectableaccording to the operation of said code bars, a second series of codebars greater in number than the number of code bars of said first seriesof code bars and selectively controlled by said individually selectablecharacter bars, a series of transmitting elements individual to saidsecond series of code bars, means for transferring a selection from saidsecond series of code bars to said transmitting elements, meansassociated with said transmitting elements for generating continuouscode combinations composed of equal length impulses at a greater ratethan the signals are received by said selector, means for generatingidle signal code combinations periodically to compensate for the greaterrate of generation of said continuous code combinations, and means forrendering said continuous i 6 code combination generating meansinoperative while said idle signals are being generated.

5. In a telegraph converter apparatus, selector means responsive tosignal code combinations, each composed of a start-stop and a series ofequal length impulses, a first series of code bars controlled by saidselector means in re sponse to the receipt of said signal codecombinations by said selector means, a series of character barsindividually selectable according to the operation of said code bars, asecond series of code bars controlled by said individually selectablecharacter bars, a series of transmitting elements individual to saidsecond series of code bars and controlled by the setting thereof fortransmitting continuous code combinations composed of equal lengthimpulses, means for en abling said transmitting elements to transmitcode combinations at a greater rate than the signals are received bysaid selector means, means for transmitting idle signal codecombinations periodically to compensate for the greater rate oftransmission of said signals by said transmitting elements, and meansfor rendering said transmitting elements inoperative while said idlesignals are being transmitted.

6. In a telegraph converter apparatus, selector means responsive tosignal code combinations, a first series of code bars controlled by saidselector means, a second series of code bars composed of a differentnumber of code bars and controlled by said first series of code bars, aseries of normal transmitting levers controlled by said second series ofcode bars for generating signal code combinations in a different codeand at a greater rate of speed than corresponding signal codecombinations are received by said selector means, a pair of idle signaltransmitting levers periodically operable to generate idle signals tocompensate for said greater rate of transmission, and means forrendering said normal transmitting levers inoperative while said idlesignal code combinations are generated.

'7. In a telegraph converter apparatus, selector means responsive tosignal code combinations, a first series of code bars controlled by saidselector means, a second series of code bars composed of a differentnumber of code bars and controlled by said first series of code bars, aseries of normal transmitting levers controlled by said second series ofcode bars for transmitting signal code combinations in a different codeand at a greater rate of speed than corresponding signal codecombinations are received by said selector means, means for periodicallytransmitting idle signal code combinations to compensate for saidgreater rate of transmission, and a divide means for determining in eachcycle of operations Whether a normal signal code combination or an idlesignal code combination will be transmitted.

MARTHA W. C. POTTS, Ewecutria: Under the Last Will and Testamen of LouisM. Potts, Deceased.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 2,273,776 Zurek Feb. 17, 19422,309,222 Spencer Jan. 26, 1943 2,352,952 Haglund July l, 1944

